Traditionally, distributed virtual environments (such as multiplayer on-line games) used rudimentary means for allowing users to communication with each other. For example, some distributed virtual environments have employed text-based communication while other virtual environments have supported simple mono voice over internet protocol technology.
It has been suggested that users' perceptions of virtual environments can be improved by augmenting the virtual environments with either medium or high quality audio communication. Consequently, considerable research has been carried out to provide distributed virtual environments with real-time immersive audio communications. Much of the research has focused on providing the users with spatial audio that conveys a perception of direction and distance; that is, the audio information sounds like it is emanating from a particular direction and has traveled a certain distance.
Research in to providing distributed virtual environments with immersive audio communication has generally assumed that users of virtual environments will use computing devices (such as a desktop computer) that have a reasonable amount of processing power and which are connected to the virtual environment server via a relatively high bandwidth data link. As such, today's immersive audio communication technology generally involves distributed immersive audio scene computations across one or more central servers and users' computing devices.
The recent uptake of portable wireless computing devices, such as the Nokia N-Gage and the Playstation Portable, means that a growing number of users will potentially want to access virtual environments via portable wireless computing devices. When compared to their desktop counterparts, portable wireless computing devices have limited processing power and will connect to virtual environments via reasonably low bandwidth wireless links. Unfortunately, today's immersive audio communication technology is unlikely to efficiently support portable wireless computing devices (or other computing devices that have relatively low computing power) because the wireless computing devices may not have sufficient processing power to participant in distributed audio scene computations. A consequence of this is that much of the computationally intensive audio scene processing will be pushed back on to the virtual environment server. This basically means that more powerful servers may need to be employed if portable wireless computing devices are to be supported and provided with immersive audio communication.